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Fridge Brilliance
Each of the Titans can be connected to the companion Sonic works with on each island:
GIGANTO is the most humanoid and fights simply yet effectively, connecting it to Amy and her role as the "human heart" in Team Sonic. Its song, "Undefeatable", is as wistful and optimistic as metalcore can get, just like Amy and her belief that love conquers all. A flashback shows that GIGANTO's pilot was the only female of the four Ancient pilots, lining up with Amy. GIGANTO also closely resembles SUPREME, just like how Amy and Sonic are both hedgehogs.
WYVERN is an awe-inspiring Titan based on mythical dragons, hearkening to Knuckles' role in a line of myths and prophecies. Its theme, "Break Through It All", reflects Knuckles' stubborn and unbreakable will that powers through no matter what.
KNIGHT is a mechanical monstrosity wielding weaponry and rolling on four legs, referencing Tails' use of gadgets such as the Cyclone to enhance his strength and mobility. Its theme, "Find Your Flame", references Tails' character arc in Frontiers about truly carving his own path as a hero, and what sort of legacy he'll eventually leave behind. "Find Your Flame" also seems to be a very contrasting song to Infinite's theme from Forces with the same singer and lyrics that basically mean opposite to each other. This can be viewed as Tails striving to become a better hero, and not try to do a repeat of what he did when Infinite attacked. "The Final Horizon" also shows its pilot to have been a curious researcher like Tails.
SUPREME is the leader who sacrificed itself to save its friends, drawing connections not only between it and Sonic, but also Sage. "I'm Here", which is also the game's main theme, works as both Sonic and Sage's theme. For Sonic, the lyrics refer to the premise of the game, exploring new and unexplored frontiers while his friends' lives hang in the balance. For Sage, the lyrics are about her developing sentience and her desire to protect Dr. Eggman.
On the topic of the Titan themes, they could also be interpreted as conversations between Sonic and the Ancients. Each one deals heavily with themes of power and competition, but also memories of the past and leaving legacies. "Undefeatable" is Sonic's boast that he can overcome the Titans, while "Break Through It All' is their rebuttal that there's much more to this adventure than meets the eye. Then "Find Your Flame" is a more literal example, as Kellin Quinn's vocals seem to embody the Ancients while Tyler Smith's embody Sonic and his friends. Then "I'm Here" is Sonic having realized the pain and trauma the Ancients went through, promising to help avenge them and help their memories live on.
Each of the island storylines involving Sonic and his friends can be seen as relating to one of The Four Loves:
Amy is Eros, or romantic love. Her subplot focuses on reuniting a Koko with its lost love, and witnessing two Ancients Together in Death. Her own love for Sonic is still present, though it's shown more subtly than is typical of the series.
Knuckles is Philia, friendship, with his island focusing on camaraderie and his Friendly Rivalry with Sonic.
Tails is Storge, familial love. Focusing on his sibling-like bond with Sonic and their Family of Choice, which triggers Sage's realization that she longs for familial love from Eggman.
Why does Eggman run into G.U.N. tech and enemies like Sonic does? Cyber Space draws from the memories of the person in it, in addition to their fears and insecurities. The only other major force Eggman has personally fought (as his armies combated the Black Arms in Shadow the Hedgehog but Eggman himself never fought them) is G.U.N., specifically from Sonic Adventure 2. Him having to deal with G.U.N. vehicles is Cyber Space drawing from his enmity with G.U.N.
Why did THE END capture Eggman, if it needed someone like Sonic to manipulate into freeing it from Cyber Space? It's quite simple really: It knows that Eggman is a dangerously intelligent mastermind, even if he's prone to letting his ego undermine him. If it were to only capture Sonic and his friends, it knows that sooner or later, Eggman's probably going to come along and find out about it, and thus potentially either find a means to control it, or just generally get in the way. After all, he's already done so in the past with the Time Eater, Infinite, Chaos, and so forth, even if things didn't go well for him in the end. By taking him out of the equation and sticking him in a place where he has no access to his technology, it basically neutralized him as a potential threat until it could escape. It just didn't factor in Sage developing beyond her original parameters and ending up becoming a threat in her own right...
This also explains why it chose to capture Sonic as well, given he's just as dangerous as Eggman, and far more physically powerful. However, THE END also chooses to manipulate Sonic over Eggman because he's much more impulsive, more prone to going with the flow, and would be too self-sacrificing and single-minded to really consider the bigger picture until it was too late.
How appropriate that a game expanding on the lore of Chaos features five of the six playable characters from Sonic Adventure, and a creation of Eggman's that Grew Beyond Their Programming.
The Titans are unique in that they are one of the only threats with a consistent ability to kill Super Sonic. Or at least, that's what it seems like before realizing that their primary methods are still Super Sonic's standard weaknesses; waiting him out by tossing him away with sheer firepower, or crushing him through various means (Giganto and Supreme's teeth, Wyvern's overwhelming rockets, and Knight's sword).
Why does Sage resemble Infinite's motifs so much? The game takes place after Sonic Forces in a way that Tails is still sour about his cowardice, meaning Eggman's total defeat is probably fresh on his mind. Between the failure of the Phantom Ruby, and the colors of both Infinite and Sage still reflecting Eggman's personal color choices, he likely subconsciously based some elements of her on his previous plans.
It's also possible that, given the Phantom Ruby's ability is described as creating a virtual reality, and her dominion is primarily Cyber Space, that she was the final project he made using it before setting his sights on The Ancients, not wanting the last of his resources dedicated to the Ruby to go to waste.
Also consider how he interacts with Sage compared to Infinite. Whereas he quickly grew exasperated with Infinite's failures and immediately disposed of him in the climax of Forces, he's a lot more patient with Sage, and though he does get frustrated by her inability to immediately free him from Cyber Space, he just limits it to complaining to vent. It's likely that after having dealt with so many failures of minions, he wanted his latest creation to genuinely like him, and so he tried his best to temper his usual behavior.
On the same note, Sage's initial color scheme undergoing a Good Costume Switch is a two-fold reference. Not only is it a partially inspired by Maria Robotnik, but it's also likely a reference to her name's original anagram, Sega, where the company's logo also has a white-and-blue scheme.
The Chaos Emeralds originating from space explains how both the Black Arms and the Babylonians were aware of them.
The Master Emerald and the Chaos Emeralds having separate origins justifies how the echidna civilization revolved around the former specifically. Knuckles shows no responsibility as the protector of the Chaos Emeralds, and the aforementioned alien groups have never shown interest in the Master Emerald.
The Ancients did, however, rely on the Master Emerald for a back-up plan. Specifically, they decided to gather the Chaos Emeralds around the Master Emerald, initially for an unexplained reason. When the operator of the SUPREME Titan had infused THE END into it, however, they decided to go along with that, while also using the other Titans to guard the islands. The Master Emerald plan was likely meant as a means to sustain the energy on Starfall Islands when they decided to move over to Angel Island.
The Ikaruga send-up in the hacking mini-game and fight with THE END is incredibly thematically appropriate to the original game. Both Frontiers and Ikaruga deal heavily with the concept of solving ages-old crises using the knowledge and hope of those who came before you, and both feature a True Final Boss against a giant, sentient stone that was previously sealed in a giant machine, and wants to erase the world in the pursuit of purity.
Why doesn't Super Sonic directly try to beat the crap out of THE END personally, only resorting to the Fastball Special with Sage to deal the fatal strike while Sage herself is the one that mainly fights in the True Final Boss? Because, raising your Attack stat aside, his battles with the Titans were already pretty brutal and they took a lot of punishment before he landed the decisive finishing attacks on them. Despite his boastful attitude and genuine invulnerability, those fights were already pushing the limits of Super Sonic; trying to beat the crap out of a Moon-sized Eldritch Abomination was likely to end poorly if he dashed in alone, especially given the battle with Biolizard on the ARK wasn't even as dangerous as this and that nearly killed Shadow, so Sage softened it up significantly. Plus, the Charged Shot of the SUPREME Titan is golden, meaning Super Sonic's still the one firing the really powerful hits as the two worked hand-in-hand the entire fight.
Super Sonic in general having a rougher time with the Titans than most other encounters before him also make sense. The most dangerous foes for Super Sonic that actually hurt him in the series were either powered by the Chaos Emerald themselves, or effectively of the God tier, such as Solaris as a god of time and space altogether, the Egg Salamander empowered as well by the Sol Emeralds and tearing dimensions apart, and the fully awakened Perfect Dark Gaia which is the negative embodiment of the entire planet. The Titans can't hurt Super Sonic, but they were made by the people who either made or directly harnessed the Chaos Emeralds better than Sonic ever did; he actually had to try instead of just ramming them at full super speed. Going into Fridge Horror as well, these bosses all have a number of Press X to Not Die moments — and they outright kill Sonic if he fails them, no matter how many Rings he has. Sonic may seem nonchalant in his victories, but these are the rare few fights in the franchise that can physically kill Super Sonic in a single attack. And if the Titans couldn't hope to stop THE END by themselves, of course Super Sonic needed the help.
What's more, by that point it was clear that the Titans were meant to combat someone with Chaos Emerald abilities, as they were designed by the Ancients, who were the Emeralds' original owners. Given how THE END clearly was able to work around Ancient anti-Chaos weapons, it doesn't take a genius to treat something already capable of overpowering technology capable of posing a fair fight to Chaos abilities, when Super Sonic is the very definition of Chaos abilities, with extreme caution.
Plus, there's the whole Running Gag of Sonic not handling sudden stops very well.
Sonic is substantially slower in this game, to the point that just running normally here is a far cry to his usual top speed in previous games. This, however, could be an indicator of Sonic trying to be more cautious in this new, dangerous environment — instead of relying on his usual breakneck speed and strength, he dials it down to a degree that, while still decently speedy, gives him more time to react to oncoming attacks and plan his moves better.
This could also be a reason why he uses more genuine combat moves instead of just boosting into and Homing Attacking enemies — trying to Homing Attack certain targets just makes them put up a barrier and stop him cold with no damage dealt. Sonic has to use new tactics to gain an edge when the otherwise tried and true method of fighting ends up negated.
This also ties into his speed buffs. As he explores the Starfall Islands and finds more Koco, he becomes more accustomed to its landscape and is comfortable ramping up his speed. When at max rings, he feels secure enough to not hold his speed back when boosting, as he won't be going down too soon if he makes a mistake. He uses more of his full speed as he becomes more confident in his ability to surpass the trials of the islands.
Why can the Parry be held down instead of having to be timed like most other games? Besides ease of use for casual players in a platformer, in-universe Sonic is still the fastest thing alive; whereas timed parries would be an act of reflexive skill for other characters, all Sonic has to do is be prepped and know something's coming and he backhands it so fast that he knocks almost anything, including beams, away from himself.
The only exceptions to this are in the DLC: the Titan Rematches of Master King's trial, and the balls of energy fired by THE END. With the latter, even if Sonic is prepared, he has to time the party just right as otherwise the attack will drain away at his Ring count, as well as the increased power of Super Sonic 2 - which is why Master King used the prior Titan fights to help train Sonic to get used to being able to parry perfectly while in his Super Sonic form.
Why do all the Cyber Space segments borrow layouts and aesthetics from previous stages in the series, specifically Green Hill, Chemical Plant, Sky Sanctuary, and Radical Highway? Considering that Cyber Space was utilized by the Ancients to archive their thoughts and knowledge, perhaps Sonic unconsciously manifested a familiar albeit still altered environment from his memories in order to better navigate through the digital world.
This is confirmed in an Ouranos Island Side Story scene, where Sonic and Sage muse about how Cyber Space is the collective memories and information of the Ancients, and that Sonic's (and Eggman's) previous experiences are interfacing with the network to project their past memories. Which leads into why Sonic was able to escape where no one else could: Sonic has bested all of his past memories quite handily, whereas Eggman and the Ancients were effectively trapped in their Darkest Hour, which isn't helped by the implication that THE END is trying its damnedest to keep Eggman contained.
Radical Highway (originally Shadow’s stage) might seem out of place among the Cyberspace stages, until you remember its appearance in the 3DS version of Sonic Generations. Though, what Sky Rail (also Shadow) is doing in there is anyone’s guess.
It's noted by Tails that he was confronted by another version of himself, who called out his poor track record and tendency to be a follower, but why is it that HE was the only one who explicitly says this happened to him, while Knuckles, Amy, or Eggman have not mentioned anything of the sort happening at all? Well, assuming THE END was involved in this, it's likely due to several factors:
1) Tails is the most devoted friend and sidekick out of everyone else to Sonic, and has basically nearly always been by his side ever since they first met. As such, this also makes him a very big target.
2) Tails has the most difficulty dealing with his internally-related flaw out of most of the cast mentioned: His confidence. Tails has always had confidence problems, and even if he managed to grow past it to some extent, it's noted that it isn't exactly consistent, with him either regressing (Sonic Forces) or overcompensating (Sonic Lost World) and everything in between. The others, while no doubt having their own internalized problems that they aren't sharing, are generally consistently confident enough to let the issue slide, or at least not let it drag them down too much. Tails on the other hand, is prone to internalizing and letting his mistakes fester, especially if he can't figure out a way around or out of it, something that would be very exploitable by something as malicious and cunning as THE END.
3) Tails is one of the potentially biggest threats to THE END outside of Sonic and Eggman (and Sage). His technical skill and ability to delve deep into information makes him, if not as dangerous as Eggman in that regard, then at the least a close second. THE END recognizes this, and would frankly prioritize doing whatever it could to make sure that Tails doesn't cause any significant damage. Additionally, tied to the above point, he's already shown signs of emotional weakness from an illusion, so why not exploit that?
Why are Amy and Sage's Memory Tokens both pink hearts? Besides the fact that their Kronos Island and Ouranos Island maps are technically the same landmass, both characters have arcs dealing with love that transcends blood and even dimensions.
THE END's form is said to be incomprehensible, and what anyone actually sees defaults what they would perceive as an omen or embodiment of death itself. The reason its portrayed as a moon is likely because many religions and beliefs throughout Earth's history have seen the moon as anything between a resting place for the dead, a wild apex predator, and a callous god willing to kill for a perceived slight. Be it peaceful, natural, or malicious, the moon is an object of death to many.
Additionally, the Space Colony Ark resembled a partial moon on one side, and Eggman used it to destroy half the moon during Sonic Adventure 2. Towards the end of Sonic Adventure 2, the Space Colony Ark nearly destroyed the world and was only stopped thanks to Sonic's and Shadow's efforts. So this could also be a very subtle nod to those events.
With The Reveal the Ancients were proto-Chao who resembled Chaos, it makes sense why Chaos, a mutated Chao, became a Blob Monster; pretty much every organism in the world has some leftover genetic traits from their ancestors. When mutated, those traits activated in Chaos - there was always genetic instructions for becoming a being of living water in Chao, it just needed the proper catalyst, more like a modern human becoming a Neanderthal than growing extra limbs (and his differences from Ancients can be justified by the fact that, as a Chao, he is still somewhat distantly related, not to mention was not born that way; there's going to be some leftover traits from his original form). This would also explain the existence of Chaos Chao, which are like a lesser-scale version of the transformation Chaos underwent.
Sonic's exploration quotes mentioning other characters are cute references to characters we haven't seen in a while such as Jet or Blaze, but they also characterize Sonic as someone who is always thinking about his friends, which is a sweet sentiment.
It should also be noted that the Cyber-Energy that Sonic's been absorbing looks suspiciously like THE END as it retreats from SUPREME, indicating that THE END has essentially seized some degree of control over Cyber Space as it was contained in SUPREME. This could also explain why Cyber Space was made so that only Sonic could escape from it, considering THE END's whole plan in the game.
The lyric "I'll find another way" from GIGANTO's theme "Undefeatable" is repeated almost verbatim by GIGANTO's pilot in the flashback, in protest to SUPREME's pilot's sacrifice.
Big paying out more Treasure Tokens for litter and junk than actual fish. It actually makes sense since cleaning up the pond would make it healthier for fish to live in and thus allow him to keep enjoying his favorite hobby for longer.
The only time THE END ever seems to move out of its emotionless state is during the final boss fight, where it launches into a "The Reason You Suck" Speech to Sonic. This makes sense, since THE END's initial plan was to leave Sonic to die after he became fully cyber corrupted, allowing it free reign to destroy everything. But then Sonic's friends sacrifice their physical forms to bring him back, which allows him to collect the chaos emeralds and face THE END. In other words, Sonic was never meant to survive his corruption, and the fact that he not only did, but also continues to defy THE END means it was genuinely pissed at him. By the time Sonic and Sage confront it in space, it's seething in barely contained rage at their presence before going all out to kill them both.
The Final Horizon revealed that Big is actually not the real Big and just a Cyber Space copy created from Sonic’s memories. This makes sense: first, we don’t know how Big got trapped in Cyber Space (both Sonic and Big lampshade it themselves); second, unlike Amy, Knuckles and Tails, we never have to rescue him either; third, Big never leaves the fishing spots; and finally, Froggy is nowhere to be seen, which is odd, since Froggy is Big’s best friend and they’re almost always seen together.
Adding to the above, despite Sonic knowing a lot of his friends as well as or as long as Big, he is the only one who shows up in Cyber Space. He is a replica from Sonic's memories, which means the fact that Sonic remembers Big appearing out of nowhere also plays into the replica!
In The Final Horizon, Sage explains that the Titans were modeled after the four tribes of the Ancients that were killed before THE END destroyed their planet. GIGANTO was based on the tribe with big and powerful bodies, WYVERN on the tribe with a tail instead of legs, KNIGHT after the tribe that walked on four legs, and SUPREME after the winged tribe. The Chao are confirmed to be descendants of the Ancients mutated by the Master Emerald, and Chaos is one that took back the form of the Ancients, with Chaos 0 strongly resembling the Ancients of the fifth tribe, the most intelligent ones. Chaos 1 and 2 have big and powerful bodies, Chaos 4 has a tail instead of legs, and Chaos 6 has four legs. The only one left is a winged Chaos form, but we've never seen what Chaos 3 or 5 look like.
Fridge Horror
The key component of what seems to cause the Chaos Emeralds to disperse after their major use and what ended up stranding the Ancients? The Master Emerald, which existed on the planet natively and interfered with the Chaos Emeralds when they were in orbit. Despite knowing where the Chaos Emeralds came from, we have absolutely no idea how on earth the Master Emerald came to be or why it interferes with the power of chaos. Which means either something even more ancient than the Ancients existed, or the Ancients themselves still acquired the Chaos Emeralds from elsewhere before bringing them here, and this could be an even greater threat to neutralize such massive, foreign power.
If the Chaos Emeralds aren't native to this series' setting of Earth, then what about the SolEmeralds? Blaze's home world is established to be a direct parallel dimension to Sonic's, right down to the two of them sharing similar roles despite their different lifestyles. So did Blaze's world always exist, and the Chaos Emeralds being introduced also brought the Sol Emeralds — or did something tear apart the fabric of reality after they came to Earth, such as THE END itself trying to escape its seal, and thus created that world?
It appears that THE END is in fact a sentient antithesis to the Chaos Emeralds, given that they embody the chaos and growth of life, while THE END represents order and neutrality. Did THE END personally seek out the Ancients in order to destroy the Emeralds? Furthermore, its tenacity in following the surviving Ancients could mean that it is possibly aware of the Master Emerald, and is thus using the Chaos Emeralds' holders as a means to an end.
On Chaos Island, there are pits with thick clouds in them that cause players to game over if they fall in them. Later it's revealed one of these pits contain The Knight, which paints a disturbing picture of what might've happened if Sonic fell in that pit.
THE END doesn't take any proper form besides the moon it shows itself as, but by Sonic standards, it's the pinnacle of Cosmic Horror Story. And it had to exist from somewhere, everything has to have an origin of some sort. So where did THE END come from? Are there more out there in the depths of space?
And on that note, did it even die when Sonic and Sage defeated it? Or is it still out there, waiting for its opportunity to strike back?
On the topic of THE END not taking any proper form aside from the purple moon, Morio Kishimoto revealed in an interview that its true appearance is... whatever the viewer perceives as "death". This affecting the player aside, it raises an interesting, yet dread-inducing question: what did Sonic and Sage see?
No wonder Chaos was so mad at his home being invaded and the Emeralds being targeted; he was a mutated remnant of the Ancients' creations, who themselves had been wiped out and sacrificed themselves to seal away THE END. So when the Echidna tribe came knocking and started killing the Chao, with what little remains of his culture and people being burned to the ground for the sake of power, he effectively was having to personally re-experience the trauma of the genocide so long ago and lost his mind to grief. Such a remnant being able to become a Physical God is a sign of what could have happened had any of the Ancients survived and lost themselves in a similar way.
Chaos used to be a Chao, and it's unlikely he personally experienced and remembers what happened to his ancestors, though he probably found out about it at some point, and thus knew that the Knuckles Clan attacking the Chao could've destroyed what was left of his ancestors, which enraged Chaos.
Even worse still is that due to the Mystic Ruins, Angel Island, and The Starfall Islands being within proximity of each other, it's implied that THE END manipulated Pachacamac into stealing the Master Emerald and kill the descendants of the Ancients, the Chao to provoke Chaos into going a rampage and forcing Tikal into sealing him away. With the last scion of Ancients out of the way, THE END can simply wait for another fool to free it, even it took centuries.
The Chaos Emeralds power everything in the Starfall Islands, and those objects then subsequently work to keep THE END's seal in place. Retroactively speaking, this means Sonic has effectively been utilizing the Ancients' work to save the world over and over — and, had the Emeralds not been disbanded naturally by the Master Emerald as a result, could've risked weakening the seal. It's arguable that the only reason it can even manipulate Sonic is because of all the times Eggman stole the Chaos Emeralds, letting bits of it leak through.
Sonic alluding to Tangle the Lemur raises a question: Is this Tangle an alternate equivalent to the one from IDW or the same one? If it's the latter, this would mean that numerous other events from IDW are now fully canon. The brainwashing of Surge and Kit, the plague of the Metal Virus, and that Eggman is capable of being a good person as Mr Tinker before being forced back to villainy by Starline are likely now canon to the game lore.
Seeing how it takes Sonic going Super to handle just one of the Titans of Starfall Islands, along with the inescapable prison of Cyber Space and the limitless knowledge it possesses, the world is lucky that Sage's concern over THE END superseded her duty to control Cyber Space for Eggman, or he would have been genuinely unstoppable.
The fact that ANY of the plots or events to destroy the planet in the past succeeding would have meant THE END being released with no one and nothing to stop them. Especially the events around Dark Gaia and Solaris. The former would have resulted in the Starfall Islands destruction and let THE END loose. While the latter would have done what THE END wanted and left himself open to be consumed by them with ABSOLUTELY no way to avoid it since its omnipresence throughout time (the only thing preventing his easy death) would be rendered null and void now that time no longer exists and only ONE of him exists.
If THE END did indeed survive by corrupting Sage, then that spells out some very concerning possibilities for Sonic's future. If it was angry enough at the Ancients for fleeing that it followed them to Earth to finish the job, it's going to be absolutely ENRAGED that a mere mortal like Sonic managed to defeat it, subsequently disproving its own philosophy about being inevitable and unavoidable. Not only that, but THE END knows all about Sonic's history and past battles, and living through Sage means it has full access to Eggman's technology. And since it knows how much Sonic values his friends and that he won't go so far as to genuinely hurt Eggman, how many different ways does it have to get back at Sonic in its current state?
In Sonic Battle, Eggman built the Final Egg Blaster, which could destroy entire star systems, solely to impress Emerl's programming so it'd define him as its master. Emerl is a Gizoid, which may still canonically be tied to the Echidnas for all we know.. who are still implied to be drawing technological advancements and capabilities from the Ancients, seeing how much their society and structures resemble the latter. While the Nocturnus Clan may be stricken from canon, this means an entity like a Gizoid was likely based off of or directly derived from Ancient origins. With that in mind, Emerl's latent capability for the Chaos Emeralds — and his super destructive capabilities at maximum power — make him seem like he was a remnant of their efforts to fight THE END in one gigantic Lensman Arms Race, producing machines that could potentially destroy the world to fight a world-destroyer.
Fridge Heartwarming
"Find Your Flame" corresponds to Tails, but the actual lyrics and perspective defy those of the previous boss themes. While "Undefeatable" is from Amy's perspective on Sonic and "Break Through It All" is from Knuckles' perspective, "Find Your Flame" at first does seem to be from Tails' perspective, as it's constantly boasting for somebody, at first presumably Sonic. A closer look at the lyrics indicates it's from Sonic's perspective, talking about Tails and tying into his character arc; he's telling Tails that he's better than he thinks he is and that he will "find [his] flame," striking out on his own to become less dependent on Sonic. The final verse specifically tells the subject character to "hear them, they're calling [their] name," which would better match with the modest, humble Tails than the highly confident, often smug Sonic.
Fridge Logic
There seems to be a similarity between the Guardian GHOST and that of the Wisps, from Sonic Colors. They both possess multiple eyes and tentacles, and their abilities are driven by energy, so it could be possible that the Ancients encountered them in some way in the past, basing the Guardian's design on them. However, GHOST can also be seen as a foil to the Wisps: while they both involve the exchange in energy, the Wisps give, while GHOST takes. GHOST's coloration and power also brings to mind Nega Wisps, and its name is a more malevolent synonym of "Wisp".
The Cyberspace stages are implied to be pulling from Sonic’s memories. So why are some of them Shadow’s stages from Sonic Adventure 2 among them? Radical Highway could be explained from its appearance in the 3DS version of Generations, though that still leaves the question of how Sky Rail is among them.
If you look up the original teaser trailer for Sonic Adventure 2, you will see Sonic in the Sky Rail stage. Considering the first DLC of this game is the Festive outfit for Sonic, which was only available as DLC on the Dreamcast release of SA 2 21 years ago, and also releasing it on December 21st of 2022, similarly deep-cut references to Sonic's presence in stages don't seem so far off.
, which are like a lesser-scale version of the transformation Chaos underwent.